From: H. Peter Anvin <hpa@zytor.com>

Date: Fri, 6 Apr 2012 16:30:57 +0000 (-0700)

Subject: x86: Use correct byte-sized register constraint in __add()

X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftip%2Ftip.git;a=commitdiff_plain;h=8c91c5325e107ec17e40a59a47c6517387d64eb7

x86: Use correct byte-sized register constraint in __add()

Similar to:

 2ca052a x86: Use correct byte-sized register constraint in __xchg_op()

... the __add() macro also needs to use a "q" constraint in the

byte-sized case, lest we try to generate an illegal register.

Link: http://lkml.kernel.org/r/4F7A3315.501@goop.org

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Cc: Jeremy Fitzhardinge <jeremy@goop.org>

Cc: Leigh Scott <leigh123linux@googlemail.com>

Cc: Thomas Reitmayr <treitmayr@devbase.at>

Cc: <stable@vger.kernel.org> v3.3

---

diff --git a/arch/x86/include/asm/cmpxchg.h b/arch/x86/include/asm/cmpxchg.h

index bc18d0e..99480e5 100644

--- a/arch/x86/include/asm/cmpxchg.h

+++ b/arch/x86/include/asm/cmpxchg.h

@@ -173,7 +173,7 @@ extern void __add_wrong_size(void)

 		switch (sizeof(*(ptr))) {				\

 		case __X86_CASE_B:					\

 			asm volatile (lock "addb %b1, %0\n"		\

-				      : "+m" (*(ptr)) : "ri" (inc)	\

+				      : "+m" (*(ptr)) : "qi" (inc)	\

 				      : "memory", "cc");		\

 			break;						\

 		case __X86_CASE_W:					\